Inductors can store/release energy under the condition of electromagnetic conversion, and the inductors may be used as elements for stabilizing current. In addition, in integrated circuits (IC), the inductors play an important role but are challenging elements. A variety of methods and techniques have been proposed for integrating inductors with IC processes. In some conventional 3D inductor devices, the main structure is constructed by plated through holes (PTHs) and surface metal circuits, and solenoid inductors are formed in a substrate.